Ruby - convert html/css to an image

hcti.rb

require "httparty"
# Retrieve your user id and api key from the Dashboard https://htmlcsstoimage.com/dashboard
auth = { username: 'user_id', password: 'api_key' }

html = "<div class='ping'>Pong ✅</div>"
css = ".ping { padding: 20px; font-family: 'sans-serif'; }"

image = HTTParty.post("https://hcti.io/v1/image",
                      body: { html: html, css: css },
                      basic_auth: auth)

# => {"url"=>"https://hcti.io/v1/image/bde7d5bf-f7bb-49d9-b931-74e5512b8738"}